Seminar Abstract

Ken Bible

Wednesday, May 18, 2005
2:00-3:30

Long-term carbon dynamics of an old-growth Douglas-fir forest

Temporal changes in forest ecosystem carbon stocks is a poorly understood
process. With relevance to global change policy and carbon
accounting and trading it is important for scientists to provide
accurate information on this largely unknown compartment of the global
carbon cycle and provide baseline data on which to establish continuous
regional and continental scale monitoring programs. At the Wind River
Canopy Crane Research Facility (WRCCRF) in south-central Washington
state, efforts are underway to measure carbon dynamics in an old-growth
Douglas-fir forest. These forests have large accumulations of biomass
and exchange significant amounts of carbon with the atmosphere. Between
1997 and 2003 the WRCCRF old-growth forest stand was on average a slight
carbon sink (0.8 Mg per hectare per year) and ranged from a minor source
(-0.5 Mg per hectare per year) to a significant sink (2.2 Mg per hectare
per year). This is counter to the long held paradigm that such
old-growth forests are large and continuous sources of carbon. Three
different methodologies for carbon measurement are employed at the
WRCCRF: traditional biophysical measurements and allometrics, stable
isotope ratio analysis, and eddy flux correlation. Each method has
inherent problems; however, they represent the best available science
for this important task.

Speaker bio:

Dr. Ken Bible began a career in forest ecosystem research in 1986
with the Uplands Field Research Lab in the Great Smoky Mountains NP
using permanent sample plots in spruce/fir forest to assess long-term
impacts of acid deposition, ozone and biological pathogens on
vegetation. He has a Ph.D. in Ecosystem Science from the University of
Washington College of Forest Resources and is currently Site Director of
the Wind River Canopy Crane Research Facility. Dr. Bible's research
interests include long-term population dynamics of tree species,
mechanisms affecting forest ecosystem structural development and
function, development and application of long-term environmental
monitoring methods, sensor arrays, and database design.